1. Field of the Invention
This invention relates to a conducting member of a disk drive suspension comprising an electronic component, such as an actuator element, and the disk drive suspension.
2. Description of the Related Art
A hard disk drive (HDD) is used in an information processing apparatus, such as a personal computer. The HDD comprises a magnetic disk rotatable about a spindle, a carriage turnable about a pivot, etc. The carriage, which comprises an actuator arm, is configured to be turned transversely relative to tracks about the pivot by a positioning motor, such as a voice coil motor.
A suspension is mounted on the actuator arm. The suspension comprises a load beam and flexure super posed thereon. A slider, which constitutes a magnetic head, is mounted on a gimbal portion formed near the distal end of the flexure. The slider is provided with elements (transducers) for accessing data, that is, for reading or writing.
In order to overcome the increase in the recording density of disks, the magnetic head should be more precisely positioned relative to the recording surface of each disk. To attain this, dual-stage actuator (DSA) suspensions, such as those disclosed in Jpn. Pat. Appln. KOKAI Publications Nos. 2001-307442 (Patent Document 1) and 2002-50140 (Patent Document 2), have been developed. One such DSA suspension combines a positioning motor (voice coil motor) and actuator element made of a piezoelectric material, such as lead zirconate titanate (PZT).
The distal end of the suspension can be moved by an infinitesimal distance in a sway direction (or transversely relative to tracks) by applying a voltage to and thereby deforming the actuator element. This actuator element is disposed on an actuator mounting section of the suspension.
The piezoelectric material is in the form of a plate, and one electrode is provided on one thicknesswise surface thereof, and the other electrode on the other surface. The one electrode is electrically connected to metallic plate member with an electrically conductive adhesive, such as silver paste. The other electrode is connected to a conducting member of the flexure by an electrically conductive member, such as a bonding wire. In some cases, as disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2011-238860 (Patent Document 3), a terminal area of a conducting member may be connected to an electrode of an actuator element with an electrically conductive adhesive.
In the terminal area, a gold plating layer is conventionally formed on the surface of a metal, such as copper or stainless steel, to enhance electrical conduction with the electrically conductive adhesive. Since gold is an inert metal, however, its adhesion to the electrically conductive adhesive is poor. In some cases, therefore, the peel strength between the electrically conductive adhesive and terminal area may be reduced in gold-plated regions. When a continuity test was conducted in a hot, humid atmosphere, for example, the electrical resistance between the terminal area and electrically conductive adhesive increased, thereby causing failure in electrical conduction to the actuator element. To enhance the adhesion between the terminal area and electrically conductive adhesive, an attempt may be made to increase the pressing force of a bonding tool so that the terminal area can be pressed against the electrode of the actuator element with a heavier load. If the pressing force increases, however, a piezoelectric material, such as PZT, may possibly be broken.
As disclosed in Patent Document 3, moreover, a proposal has been made to apply laser light to a gold plating layer, thereby forming a large number of irregularities on the surface of the plating layer. Since the gold plating is made of an inert metal, however, formation of the irregularities as a measure to enhance the adhesion to the electrically conductive adhesive leaves room for improvement.